Japanese architect Sou Fujimoto is known for designing unique homes that are filled with natural light, but his latest design, House NA in Tokyo, trumps all. The small, unconventional home is made almost entirely of glass with a white steel frame, making it virtually transparent, and blurring the line between indoor and outdoor space. The house challenges our typical understanding of what a house should be, and it gives its inhabitants the freedom to move around the house, using different spaces as they see fit.

What makes House NA so unique is that it doesn’t contain rooms in the same way that most typical homes do; instead, it has 21 different “floor plates” of varying sizes that flow into each other. Fujimoto likens the house to a tree, with the 21 different spaces acting like high and low branches on which people can perch. “The intriguing point of a tree is that these places are not hermetically isolated but are connected to one another in its unique relativity,” he writes.

In contrast to the concrete block or wood walls found in a typical home, House NA, which is made almost entirely of glass, appears light and airy. With all of that glass, the house doesn’t naturally afford much in the way of privacy, but curtains can be installed, both as a partition between rooms, and to provide privacy. Some of the spaces in the 914 square-foot home are heated, while others are not. The three-story house also features several balconies without safety rails, enhancing the minimalist aesthetic.